U.S. Pat. No. 3,773,153 discloses a fabricated friction disk in which the outer parts are manufactured of steel and the core is made of corrugated aluminum plates.
The manufacture of disk outer parts from steel, with the same physical and mechanical properties over the entire friction surfaces, does not ensure uniform resistance to the destruction of different zones of the friction surfaces under the action of high temperature and mechanical stresses. Furthermore the use of steel in disk outer parts does not aid in damping oscillations and eliminating rattling during braking, the factors which adversely affect the serviceability of the unit.
From P. I. Orlov, "Fundamentals of Design", Reference handbook, Book 1, 1988, p. 131, it is known that the low strength and rigidity of light alloys prevent their use in support structures. For example, rolling bearings built in units made of light alloys are recommended to be mounted with the use of intermediate steel sleeves.
However, employment of reinforcing sleeves requires the increased expenditure of materials, increases the weight of construction and does not ensure optimum carrying capacity of the friction surface, tightness of the joint and resistance of the bearing to pressing out forces, thus reducing the service life of the friction disk.
SU, A,846875 discloses a friction element of a friction pair, which is essentially a brake disk comprising a three-dimensional framework, embedded in a matrix made from a material with a high coefficient of thermal conductivity. Each of the friction face surfaces of the disk is coated with a layer of wear-resistant material.
In the course of braking, heat is generated, which is removed from the disk friction surfaces by means of a liquid heat-transfer agent circulating in the framework.
However, since the load and heat stresses acting upon the friction surfaces in different zones are not uniform, and the properties of the friction material are the same over the friction surfaces, it is impossible to ensure uniform resistance to the destruction of different zones of the friction surfaces and to avoid rattling which results in premature failure of the disk.
Wear-resistant coating applied to the friction surfaces of the disk does not ensure their optimum carrying capacity.